I am making a portal where authorized users can upload videos, and have other users watch them in browser. Originally, I decided on using an HTML5 player with MP4 format, however I have since discovered MP4's expensive licensing requirements. At present I am considering still using the HTML5 player with Ogg format, and using flash player with .flv format as a backup for IE. This is for an educational non-profit institution, and all videos uploaded will be instructor created for educational purposes, however the content will only be available to students.
I would like to confirm there are no licensing requirements on .flv format usage. My research has indicated this is not the case, however I wish to be certain.